The present invention is related to a string-pulling device of a racket-stringing apparatus, and more particularly to a string-pulling device of a racket-stringing apparatus, which can be conveniently maintained and repaired.
FIG. 5 shows a conventional racket-stringing apparatus 7 composed of a bed 71, a racket stringer 8 and a string-pulling device 9. The racket stringer 8 and the string-pulling device 9 are side by side mounted on the bed 71. The racket frame is fixed on the racket stringer 8 for stringing the racket frame. The string-pulling device 9 has a string-pulling head 91 rotationally drivable by a driving unit (not shown) mounted in the string-pulling device 9. A control panel 92 is arranged on outer face of the string-pulling device 9. The control panel 92 via a control circuit is connected with the driving unit for controlling the rotation of the string-pulling head 91.
In use, the racket frame is fixed on the racket stringer 8 for stringing the racket frame. The string passing through the racket frame is chucked in the string-pulling head 91 of the string-pulling device 9. By means of operating the press buttons of the control panel 92, the driving unit is activated to rotate the string-pulling head 91 for adjusting the tension of the string.
The control panel 92 is fixed on the string-pulling device 9 and via wires connected with the control circuit in the string-pulling device 9. Therefore, it is hard to disassemble the control panel 92. As a result, in practice, the racket-stringing apparatus 7 often has some shortcomings as follows:                1. The stringing operation is a long-term work and repeatedly performed. Therefore, the racket-stringing apparatus is easy to wear out. Especially, due to the temperature and humidity of the working site, the parts of the control circuit of the control panel of the string-pulling device tend to damage after a period of use. Once the control circuit of the string-pulling device is damaged, it will be impossible for an operator to string the racket frame. Under such circumstance, it is necessary to repair the control circuit. However, the control circuit is laid in the string-pulling device. Therefore, the entire racket-stringing apparatus must be sent back to the mother factory for service. Alternatively, the mother factory must send a specialist to repair the racket-stringing apparatus. In the case that the racket-stringing apparatus is sent back to the mother factory, the delivery cost will be huge and it is time-consuming and laborious to move the entire racket-stringing apparatus. In the case that the mother factory sends a specialist to repair the racket-stringing apparatus, the cost for the reparation is also enormous.        2. Some data such as rotational speed and tension value are preset in the memory of the control circuit of the string-pulling device for repeated stringing operation. Therefore, it is unnecessary to re-input these data and the string can be pulled under unified tension. In case that the control circuit of the racket stringing apparatus fails, it will be necessary to repair or replace the control circuit. After the control circuit is replaced, the original data of the memory cannot be accessed. Therefore, after repaired, it is necessary to reset the data. This is quite inconvenient and troublesome.        